Over the past year, two studies have been completed to the point of publication. The first examined the mechanisms by which blood flow and glomerular filtration are controlled. The results strongly suggest that the composition of the fluid reaching the late portion of the renal tubule serves as a feed-back type of regulator or GFR and renal vascular resistance. The second study examined the effects of ADH on distal tubular fluid osmolality and sodium concentration. This study provided a greater insight into possible mechanism by which ADH enters into the conversion from water deprivation to water diuresis.